Air-compressor.



0. DAY & G. WINDELER. AIR COMPRESSOR.

APPLICATION FILED JUNE 13, 1912.

1,088,265, Patented Feb. 24, 1914.

2 SHEETS-SHEET 1.

came/.54 Dar qzonqs E W/NDELER 0. DAY & G. E. WINDELBR.

AIR COMPRESSOR.

APPLIOATION FILED JUNE 13, 1912.

1,088,265 Patented .Feb. 24, 1914.

2 SHEETS-SHEET 2.

WITNESSES INvEN-roRs CHARLES DAY G a'oaqa E.WlNDEl-EF ATTORNEY UNITED STATES PATENT OFFICE. v

CHARLES vDAY AND GEORGE E. WINDELEB, OF STCCKPORT, ENGLAND, ASSIGNORS T0 GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

AIR-COM'BRESSOR.

Specification of Letters Patent.

Patented Feb. 24, 1914.

Application filed June 13, 1912. Serial No. 703,394.

To all whom it may concern Be it known that we, CHARLES ,DAY and GEORGE E. "WINDELE-n, subjects of the King of Great Britain, residing at Stockport, county of Cheshire, England, have invented certain new and useful Improvements in Air-Compressors, of which the following i a specification.

Our invention relates to multi-stage reciprocating air compressors and has for its object to improve their construction.

For a consideration of What we consider to be novel and our invention, attention/is directed to the accompanying description and claims appended thereto.

In the accompanying drawings, which are illustrative of our invention, Figure 1 is a vertical section of a two-stage air compressor; Fig. 2 is a plan view, partly in section, of the valve chest of the low pressure stage;

Fig. 3 is a detail view showing the port admitting air to the valve chest; Fig. 4 is a detail sectional view of the valve chest, and Fig. 5 is a detail sectional view showing the means for conveying cooling water from the cooling chambers of the low pressure cylinder to the cooling chamber in the valve chest.

6 indicates the cylinder of the low pressure stage, and located therein is a liner 7 that is provided with an annular flange 8 which rests on the top of the cylinder. Between the cylinder wall and the liner are vertical chambers 9 and 10 containing cooling water. These chambers are connected by a relatively small annular passage 11, the arrangement being such that the cooling wa ter passes through the opening with a fairly high velocity. Cooling water is admitted to the chambers by the ports or passages 12. Located within the liner is a low pressure piston 13 of any suitable construction, said piston being provided with piston rings 14. Integral with the low pressure piston or secured thereto is a high pressure piston 15, formed upon a rod of uniform diameter with the high pressure cylinder and having packing rings 16 at its outer end of any suitable construction.

Mounted on top of the low pressure cylincasting is provided with vertical walls or partitions forming a segmental shaped suction chamber 19 and a discharge chamber 20.

The former is in communication with the inlet port ,21 and the latter with the discharge port 22. Air from the port 22 will usually be passed through a cooler before entering the suction valve or valves of the high pressure stage. In the inlet chamber is located a plurality of suction valves 23, and in the discharge chamber 20 is located a plurality of discharge valves 24 of the construction best shown in Fig. 1.

Referring toFig. 1, 23 indicates a thin disk valve, and 25 the seat therefor containing a row of ports 26 which are in communication with the supply or suction cham ber 21. 27 indicates a stop for limiting the opening of the valve, said stop being tubular in form and chambered out to receive the coiled compression spring 28, the latter tending to hold the disk valve 23 against its seat.

In the stop are ports 29 which convey air to the cylinder space,. said ports connecting with the passage 30. The passage 30 while relatively thin extends over a large area so that air will freely enterthe cylinder space. It is common to all of the suction valves, of which three are shown. Said stop 27 is provided with an external shoulder that is seated on a shoulder formed on the casing. The stop is held in place by the valve seat 25 and the latter is secured by the screw threaded plug 31. By removing the plug the valve parts can be readily removed and replaced through'the plug covered opening, said parts being smaller in diameter. This is an important feature because all the valves of an air compressor should be examined at rather frequent intervals to see that they are in perfect working order, and the securing means should be simple.

Air is admitted to the supply chamber by a pipe 32 having a plurality of radial slits 33, the arrangement being such that a large volume of air can be supplied with a minimum disturbance and foreign matter prevented from entering the compressor. The

hand wheel 35 for adjusting the position of the valve with respect to its seat. After the valve is adjusted it is held in position by the lock nut 36.

The discharge valves 24 are similar in construction to the suction valves but are reversed with respect thereto. The spring 28 for seating each valve has been omitted because it is unnecessary, the pressure on the discharge side acting to seat the valve on the suction stroke of the piston 14. Under some conditions it will be found satisfactory to omit the springs 28 from the suction valves. Each discharge valve .is held in place by a bolt 37 which passes through a, screw threaded plug 38 and engages the upper end of the valve stop 39, the latter being provided with ports connecting with the discharge chamber 20.

It is of the utmost importance to properly cool the valves of the compressor and also to cool the air as muchas possible. To. this end the valve chest is provided with a'.

cooling chamber 40 which isformed by cores at the time the casting is made. In order to completely remove the core material the central part of the valve chest is made with a relatively large opening, the surfaces of which are subsequently machinedto receive the closely fitting sleeve 41. The sleeve which forms a wall of the cooling chamber is provided with an annular flange that is seated in the upper wall of the chest. Said sleeve is held in place by a number of screws 42, Fig. 2. Cooling water is conveyed from the chamber 40 to the cooling chamber 43 around the high pressure piston by fittings 44. These fittings are 'made out of short pieces of tube threaded at their lower ends and each provided with an annular shoulder that engages the top surface of the flange on the sleeve. Between these shoulders and a part of the high pressure cylinder are packings 45 to prevent the escape of water. The bolts that secure the high pressure cylinder to the valve chest also serve to compress the packing 45. It will thus be seen that the-arrangement affords a very simple means for conveying water from one cooling chamber to another. A similar arrangement is shown in F ig. 5 for conveying cooling water from the chamber 9 to the chamber 40 in the valve chest. In'this fi 'ure, 6 indicates the low pressure cylinder, the liner therefor, and 8 the annular flange of the liner. In this case the fitting 44 is made longer and is threaded into the cylinder 6. It is provided with a shoulder that engages the top surface of the flange 8 of the liner, and between this shoulder and the bottom wall of the valve chest is a packing 45. This packing is held under compression by the stud bolts which secure the valve chest to the low pressure cylinder.

from leaking out around the bolts 18 which clamp the valve chest to the low ressure cylinder, tubes 46 are employed as s own in Fig. 4. These tubes are made out of thin brass or copper and are expanded into holes in the valve chest to makewater-tight joints. At the left of the tube in Fig. 4 is shown one of the openings 47 to receive the fittin 44of Fig. 5. f v Re erring again to Fig. .1, 48 indicates the high pressure cylinder which is provided with a liner 49 that is provided with a flange 50 at its u per end, said flange rest- In order to prevent the circulating water ing on an interna shoulder formed on thecylinder casting. If desired the liner can be cast as an integral part of the cylinder, as may also that of the low pressure cylinder. The liner is held in position by the lower end of a valve casing 51, said end be ing provided with a projection that fits into a groove in the upper end of the liner. The valvecasing is' provided with a flan e that rests on the top of the cylinder an is secured thereto by bolts 52. Located in the casihg are one or more suction valves 53 and one or more discharge valves 54 which are of the same general construction as the suction and discharge 'yalves of the low pressure cylinder; they are, however, somewhat smaller because the volume of air to be handled'is less. The portion of the cylinder casting surrounding the valve casing is provided with coolin chambers 55 that are connected with the c iamber 43 and contain cooling water, said water being discharged by the port 56. The. high pressure cylinder is secured to the valve chest by bolts 57 and hence it can be removed without disturbing the low pressure valve chest. It will also be seen that the high pressure valve chest or casing 51 can be removed without disturbing the high pressure cylinder.

Owing to the particular construction of the low pressure valve chest heretofore de-. scribed, it will be seen that all of the core material can be completely removed and that when the sleeve 41 is taken out, access will be had to the interior of the valve chest for the purpose of cleaning out the chamber .40 which contains the cooling water. It is essential to the best operation of such a compressor to keep this chamber free from mud and other impurities conveyed by the circulating water. Owing to the arrangement of the cooling chamber 40 as specified, the valves will be separately cooled and the air passing through them will also be cooled to a greater or less extent. It will also be observed that the valve chest forms a distance piece to preserve the proper distance between the low and high pressure cylin- 'ders,.that it forms a cover for the low pressure cylinder and that it permits of the use of a series of valves located in such positions that the air can freely pass to and from them. Owing to the relatively large space between the valves, ample cooling facilities are provided.

By "making the valve chest as a separate unit, it can be separately machined and pressure tested, which is of great advantage from a manufacturing point of view.

It also sim lifies the casting operation and the form 0? the patterns, as will readily be understood.

The invention .is not limited to a twostage compressor but can be utilized in compresso-rs having a greater number of stages. In so far as our invention is concerned the air entering the valve chest may have been previously compressed. I

In accordance with the provisions of the patent statutes we have set forthwhat we believe to represent the best embodiment of our invention; but it is to be understood that the drawings are only illustrative and that our invention can be carried out by other means.

lVhat we claim as new and desire to secure by Letters Patent of the United States is 1. In an air compressor, the combination of a low pressure cylinder, a valve chest hav ing a cooling chamber therein, valves therein, means for circulating water through said chamber, a sleeve mounted in the chest that forms one wall of the chamber, a high pressure cylinder that extends through the sleeve, and pistons for the cylinders.

2. In an air compressor, the combination of a cylinder, a valve containing chest mounted thereon which forms its cover a cooling chamber in the cylinder, acooling chamber in the valve chest, a .fitting that connects the cooling chambers, a packing around the fittings, and .bolts for securing the chest to the cylinder that also serve to compress the packing.

3. In an air compressor, the combination of a cylinder casting, a liner located therein and separated therefrom on its sides to form a cooling chamber, a valve containing chest that is mounted on the cylinder and forms the cover thereof, partitions in the chest that divide it into air and cooling chambers, a plurality of fittings that extend through the walls of the cylinder and chest and establish communication between the cooling chambers, and means for uniting the cylinder and chest that also hold the fittings.

4. In an air compressor, the combination of a cylinder, a chest mounted thereon which also forms its head, partitions in the chest that form segmental suction and discharge chambers, inlet and outlet ports therefor, valves in the chambers, a cooling chamber which incloses the suction and discharge chambers, and a sleeve located in the center of the chest which forms one of the walls of the cooling chamber.

5. In an air compressor, the combination of a low pressure cylinder, a valve chest mounted thereon which forms its head, a high ressure cylinder that is supported by the c est and extends through it into communication with the low pressure cylinder, a low pressure piston, a high pressure 'piston mounted directly thereon, valves in the chest which communicate directly with the loW pressure cylinder, means for securing the chest to the low pressure cylinder, and other means for securing the high pressure cylinder to the chest.

6. The combination of a low pressure cylinder, a high pressure cylinder in line therewith, pistons for the cylinders, the high pressure piston being formed from an extension of thelow pressure piston of uniform diameter with the high pressure cylinder, a

valve chest connecting the cylinders, castings containing chambers surrounding the cylinders, and liners forming the working surfaces of the cylinders and the inner walls of the chambers, as described.

7. The combination of a low pressure cylinder and a high pressure cylinder, each comprising a casting having a cooling chamber therein and forming the outer wall and a liner forming the inner wall, a valve chest formed of a casting having a cooling chamber therein and forming a rigid connection for said cylinders, suction and discharge valves in said valve chest and ducts connecting all said cooling chambers.

8. As an article of manufacture, a valve chest comprising top, bottom and peripheral walls, partitions in the chest which divide it into suction, discharge and cooling chambers, and a removable sleeve that forms a cylindrical central wall for the cooling chamber.

9. In an air compressor, the combination of a cylinder, a valve containing chest which forms the cover therefor, and contains a central opening, a cylinder mounted on top of the chest which projects into said opening, said cylinders communicatin with each other, pistons located in the cy inders which differ in diameter and are mounted one on the other, a head for the second cylinder, and suction and discharge valves mounted therein.

10. Iii an air compressor, the combination of a'low pressure cylinder comprising a casting forming the outer wall thereof and a liner forming the inner wall with a cooling chamber therebetween, a valve chest mounti ed'on said low pres sure cylinder. comprising In witness whereof we.have hereunto set a .casting having formed therein valve our hands this 23rd day of May, 1912.

"chambers a d a cooling chamber, a removable sleeve BEOI'IIliIlg the inner wall of said g g g g fi 2% 5 cooling chamber, suitable suction and dis- I charge'valves mounted in said valve cham- Witnesses: 'bers, and a fitting connecting the cooling ALEX. F. MACDONALD,

1 chambers JOHN, W. GILL.

come: of this patent may be obtained for five cents each, byaddreuing the Commluloner o! ratentl, Washington. D. 0. 

